And Now, the Dream of a Harris-Buttigieg Ticket

Two new Democratic stars outshone Biden and Sanders on the debate stage.

The big question going into Thursday night’s debate was whether Joe Biden, the clear front-runner in the race for the Democratic presidential nomination, would stumble.

That turned out to be the wrong one. The right question was whether he had sufficient vigor in his stride.

And the answer came in watching Kamala Harris and Pete Buttigieg — two of the event’s standout performers — run articulate and impassioned circles around him.

Biden was O.K. Not bad, not good: O.K. He didn’t crumble under some tough interrogation from moderators — about his vote for the invasion of Iraq, for example — and occasional attacks from his rivals onstage.

But in his determination to prove how coolheaded he could be, he frequently turned his temperature down too low. In his insistence on not getting tangled in grand promises or lost in the weeds, he too often kept to the side of the field.

At one point, when candidates were asked to raise their hands if they believed that crossing the border without documentation should be a civil rather than criminal offense, his gesture was so tentative and ambiguous that one of the moderators, José Díaz-Balart, had to follow up: Was he indicating his assent or seeking permission to make a comment?

That was a metaphor for his whole night.

Other candidates demanded that America march forward. Biden kept looking backward. He repeatedly alluded to his decades of experience and even more pointedly reminded voters of his eight-year partnership with President Barack Obama, a towering and popular figure in the Democratic Party. While Bernie Sanders pledged a revolution, Biden promised a restoration.

Will that make voters feel tingly enough? It’s possible, given the ongoing trauma of the Trump years.

But the debate brought into vivid relief the shortcomings of his candidacy and the risks of graduating him to the general election.

When you’ve been in politics and in Washington as long as he has — 36 years in the Senate, plus eight as vice president — there are votes from eras much different from the current one, controversial positions galore and mistakes aplenty. All of these were ammunition used against him on Thursday night, most electrically when Harris pressed him to defend his opposition to busing to integrate schools.

Harris made it personal, telling him that she got the education she did because of busing. Biden said that he hadn’t been opposed to busing so much as in favor of local decision-making, and he thus left himself open to her righteous response: Did he not think that the federal government should swoop in to remedy obvious racial injustice?

“That’s why we have the Voting Rights Act and the Civil Rights Act,” she said. “Because there are moments in history where states fail to preserve the civil rights of all people.”

One of these two candidates was in much better sync with Democratic voters right now, and that candidate was Harris, a black woman who, at 54, is more than two decades younger than Biden, who is 76. The only candidate on the stage older than him: Bernie Sanders, 77.

And the sense of a generational divide was acute, partly because Buttigieg, 37, and Eric Swalwell, 38, made sure to highlight it. At the very start of the night, Swalwell noted mischievously that Biden had long ago stressed the importance of passing the torch, and Swalwell exhorted Democrats to do precisely that, saying “pass the torch” so many times that Díaz-Balart asked Biden, “Would you like to sing a torch song?” Biden then rattled off a few canned remarks about the importance of education.

Biden and Sanders stood at the lecterns in the center of the stage, their prize for having significantly higher poll numbers than the others. They were supposed to be the pace setters.

But they receded more than they popped. Maybe that was a function of familiarity. I couldn’t detect any difference between Sanders now and Sanders four years ago: The mad gleam, bad mood and hoarse-from-yelling voice were all the same. A screenwriter friend of mine emailed me midway through the event to say that Sanders resembled “a very angry chess player in Washington Square Park in an undershirt and madras shorts in the summer heat.” He did indeed look steamed.

Buttigieg didn’t. He has this way — it’s quite remarkable — of expressing outrage without being remotely disheveled by the emotion, of taking aim without seeming armed, of flagging grave danger without scaring the pants off you. He’s from some perfect-candidate laboratory, no?

And nobody onstage spoke with more precision and shrewdness, though Michael Bennet came close a few times. Buttigieg said that the God-garbed Republican Party, in its treatment of migrants, “has lost all claim to ever use religious language again.” It wasn’t just a dig; it was a deft reminder of his public fight with Mike Pence over Pence’s vilification of L.G.B.T. people like Buttigieg.

On the subject of health insurance, Buttigieg said that sick people “can’t be relying on the tender mercies of the corporate system.” He spoke of China “using technology for the perfection of dictatorship.” Phrases like these came like candies from a Pez dispenser — colorful, sweet and one after the other.

And when Buttigieg was confronted with questions about the recent police shooting of a black man in South Bend, Ind., where he is mayor, and asked why the police force wasn’t better integrated, he admitted, bluntly: “Because I couldn’t get it done.He didn’t make excuses, instead recognizing that between African-Americans and white police officers, “There’s a wall of mistrust, put up one racist act at a time.”

Harris had a fire that Buttigieg lacked, and it was mesmerizing. She challenged Biden not just on busing but on sloppy recent comments of his that seemed affectionate toward segregationists. She picked apart Trump’s boasts of a spectacularly booming economy, telling the right number of right anecdotes at the right time.

And she mixed strength with warmth and even humor. As candidates shouted over one another in a lunge for microphone time, she found a cranny of oratorical space in which to land a good line. “Hey, guys, you know what?” she said. “America does not want to witness a food fight. They want to know how we’re going to put food on their table.” It neatly pegged men as compulsive interrupters — a leitmotif of the previous night’s debate — while flying a feminist flag less strenuously than Kirsten Gillibrand, at the lectern beside hers, did.

Imagine a Harris-Buttigieg ticket, and not only what a wealth of poise but what a double scoop of precedents that would be. Plenty of people on Twitter on Thursday night were doing precisely that.

Plenty more will do so in the coming days, and they should leaven that fantasy with a reality check about how far to the left Harris in particular has moved. She was one of just two candidates on Thursday night who said that she wanted to do away with private health insurance. Sanders was the other. And that could be a general-election problem for her, as it could for Elizabeth Warren, who took that same position the night before.

But I write now in praise of a commanding performance that easily overshadowed Biden’s, with his herky-jerky delivery and his reflexive glances in the rearview mirror. Elections, according to all the political sages, are about the future. Biden didn’t seem to be pointed in that direction, and he didn’t demonstrate any sense of hurry to get there.